Research And Practice On SFN Of Digital Television Terrestrial Multimedia Broadcasting

DTMB (Digital Television Terrestrial Multimedia Broadcasting), based on DMB-T of Tsinghua University, ADTB-T of Shanghai Jiaotong University, and TiMi of Academy of Broadcasting Science, was released as the national standard on Dec.6,2011and has become the fourth International standard since America, Europe and Japan put forward theirs. The SFN (Single Frequency Network) is an important networking of DTMB. From the viewpoint of the exploitation of frequency resources and signal coverage, it has more obvious advantages than MFN (Multiple Frequency Network). However, DTMB hasn’t been spread widely in China because, as a digital terrestrial transmission system and under various geographic conditions, it requires advanced technology, complicated signal processing and difficult system debugging. Meanwhile, DTMB is an integration based on single carrier and multiple carriers, which needs to avoid exclusive effects resulting from this integration.In this dissertation, the state-of-the-art development and application of International digital television terrestrial broadcasting is first reviewed. Four International standards are compared. And more, the uneasy way the DTMB was developed in China and the important significances of the study on terrestrial digital broadcast SFN are discussed.Then, on a basis of synchronization theory, system s(?)ucture, program design and system debugging on DTMB, SFN system compositions, core technology of TDS-OFDM, and SFN designing planning methods are deeply analyzed.Next, the design and implementation of the first digital terrestrial television broadcasting test platform attached to Jiangxi Broadcasting and Television Bureau is introduced. How to tackle the technical problems of the big circles of radio frequency signals overlapping the small ones under special geographic and construction environment is also discussed in detail.Finally, the key points of the SFN technology, i.e., the problem of interference in the overlapping area, are explored and a number of technological optimization solutions for signal coverage of the SFN are proposed.